Headlight.



F. F. MACLEAN- HEADLIGHT.

APPLICATION FILED DEC. 30. 1914.

l 146,26 Patented July 13, 1915..

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FREDRICK F. MAQLEAN, F SYRACUSE, NEW YORK.

HEADLIGHT.

Specification of Letters Patent. Patentgdl July 13 1915 Application filed December 30, 1914. Serial No. 879,782.

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To all whom it may concern:

Be it known thatzI, FREDRICK F. MAC- LEAN, a citizen of the United States, and resident of Syracuse, in the county of Onondaga, in the State of New York, have invented new and useful Improvements in Headlights, of which the following, taken in connection with the accompanying drawings, is a full, clear, and exact description.

This invention relates to certain improvements in head lights for automobiles, motor boats and similar vehicles in which an incandescent electric lamp is used in conjunction with a reflector for projecting an intensified light forwardly in the path of travel of the vehicle, and while this aflords a clear vision of the roadway and distant objects ahead of the machine at night, the glare of the light is seriously objectionable to approaching horses, pedestrians and drivers of other vehicles in producing a more or less blinding eflect upon the eyes with attendant dangers of accident.

I am aware that various devices have been proposed to screen ordeflect the direct or reflected rays of light in head lights of this character so as to obviate the objectionable results referred to, and while that is the primary object of my invention, the specific object is to incorporate the screening or light intercepting elements in the bulb of the lamp in such manner as to permit an intensified light to be projected the usual distance forwardly along and upon the surface of the ground in advance of the machine but below the normal plane of vision of approachlng drivers, horses or pedestrians, and at the same time to afford a subdued light throughout the remaining portions of the field of reflection.

Another object is to enable this lamp to be used in connection with any form of reflector for producing the results above referred to.

Other objects and uses relating to specinc parts of the bulb will be brought out in the following description.

In the drawings Figures 1, 2 and 3 are diagrammatic views of my improved head light as used in connection withan approximately spherical reflector in Fig. 1 and parabolic reflectors in Figs. 2 and 3, the lamp in each figure being located in the focal axis of the reflector but in such relation to the focus of such reflector as to cause the rays of light passing through the transparent portions of the bulb to be reflected and projected forwardly mainly below the plane of vision of an approaching driver, horse or pedestrian and partially above such plane, the main translucent intercepter of the bulb being shown as inverted in Fig. 3 for the purpose of causing the greater portion of the reflected rays to be projected forwardly in approximately parallel lines or slightly diverging lines. Fig. 4 is a front end view of the lamp bulb. Figs. 5, 6 and 7 are, respectively, a side elevation and opposite plan views of the same bulb.

The bulb 1 is preferably spherical and provided at its rear side with a suitable plug 2 adapted to be inserted in a correspondingly formed lamp socket, not shown, said bulb containing the usual incandescent filament 3. The front side of the bulb is provided with a translucent portion l of relatively small area and preferably of triangular form as shown in Fig. 4: with the center of the triangle approximately coincident with the forwardly projecting axis of the bulb. One of the rear quarters of the bulb is provided with a translucent body 5 extending partially across the rear side of the other rear quarter of the bulb. as shown more clearly in Figs. 5 and 6 thus leaving an intervening zone ,7 of clear transparent glass between the translucent portions 4: and 5, the transparent area approximating three-quarters of the area of the bulb and extending continuous around the same at right angles to its for-- wardly projecting axis so that approximately one quarter of the area at one side of the horizontal plane of said axis is transparent while approximately one-half of the area of the bulb at the opposite side of said plane is also transparent.

When the lamp is used in connection with a substantially spherical congerging reflector as -a Fig. 1, it is so arranged with reference to the focus of said reflector as to cause the reflected rays passing through the transparent portion of the bulb to be converged at a point in the produced axis of the reflector at a short distance in front of the same, so that the continued rays projecting beyond said point diverge downwardly in a plane below said produced axis upon the surface of the ground or path of travel of the vehicle a considerably farther distance 110 in advance of the lamp or vehicle, and wholly below the plane of vision of an approaching driver, horse or pedestrian, and for this purpose the translucent intercepting zone 5 of the lampis disposed with its major portion below the horizontal plane of the axis of the lamp while the relatively smaller zone 4: will be located in said axis, thereby permitting portions of the direct rays from the incandescent filament to be projected forwardly and downwardly through the transparent zone 7 directly in front of the machine or vehicle, and also below the axis of the reflector. llt is also evident that in the construction of reflector shown in Fig. 1, portions of the direct rays from the incandescent filament will be projected upwardly in front of the reflector considerably above the plane of vision of an approaching driver, thus producing a sufficient amount of spilled light to illumine the environs of the reflector.

For convenience of description, the front and rear ends of the bulb may be termed the poles and the translucent portions at such ends may be termed the translucent polar zones, while the main body of the translucent portion 5- may be termed the semi-equatorial zone merging with the rear polar zone while the main body of the transparent portion 7- may be termed the circumferential transparent zone interposed between the translucent polar zones.

In Figs. 2 and 3, the lamp is used in connection with a parabolic reflector -b,, the semi-equatorial zone 5 being shown in Fig. 2 as located at the lower side of the bulb and in front of the focus of the reflector, while in Fig. 3, it is shown as located at the upper rearside of said bulb and just at the rear of the focus of the reflector so .as to cause the rays of light passing through the transparent zone at the lower side of the bulb to be reflected forwardly in approximately parallel lines wholly below the produced axis of the reflector, while the direct rays emanating from the incandescent filament will be projected in forwardly diverging lines through the transparent portions of the bulb around the edges of the translucent polar zone -i. The translucent zones may be formed by depolishing, sandblasting or otherwise treat ing these portions of the bulb so as to increase their light absorbing power to such an extent as to render them translucent for the purpose of subduing the intensity of the light to the desired degree without color.

I have mentioned that the lamp shown in Fig. 3 is located just at the rear of the focus of the reflector, the object of which is to cause the reflected rays of light to project forwardly in slightly diverging lines, but it is evident that the lamp might be located exactly at the focus of the reflector so as to menace cause said rays to be reflected forwardly in parallel lines. I have also mentioned-that the lamp in Fig. 2 is located in front of the focus of thereflector,the objechof which is to cause the reflected rays from the upper portion of the reflector to be projected forwardly in downwardly converging lines meeting at a point a short distance in advance of the head light to cause the continued rays to be thrown upon the ground a still farther distance in advance of the machine, but wholly beyond the plane of vision of an approaching driver, horse or pedestrian. It is, therefore, evident that the lamp may be used with equal efficiency in connection with the approximately spherical reflector shown in Fig. 1 or with the parabolic reflectors shown in Figs. 2 and 3, and that the lamp may be placed in such manner as to bring the translucent zone 5 either above or below the horizontal plane of the axis of the parabolic reflector, but when used in connection with the spherical reflector, the translucent zone 5 should be located below the plane of said axis so as to throw the rays of light forwardly and downwardly upon the surface of the ground in front of the machine and in a plane wholly below the plane of vision the driver of an approaching machine or of an approaching horse or pedestrian.

What ll claim is 1. In a head light for vehicles in combination with a reflector, an incandescent electric lamp having its front portion provided with a translucent polar zone intercepting 1 said axis and a semi-equatorial translucent zone mainly in the plane at the rear of the source of light, portions of the bulb etween the translucent zones being transparent.

2. In a head light for vehicles in combination with aireflector, an incandescent electric lamp having a substantially spherical bulb provided with a front translucent polar zone of relatively small area, a rear trans luoent polar zone and a semi-equatorial translucent zone merging with the rear translucent zone, the portions of the bulb between the semi-equatorial zone and front polar zone being transparent.

3. The combination with a converging reflector of an incandescent electric lamp therein havlng approximately one quarter of the area of the bulb nearest the socket and a relatively smaller area at its front plane near that of the center of the bulb, the portions of the bulb in front and at one side of the semi-annular zone being transparent.

5. In a headlight, a reflector and an incandescent lamp bulb having an annular translucent polar zone at its base and a semi-annular translucent zone merging with the first named zone and terminating in a plane near that of the center of the bulb, the portions of the bulb in front and at one side of the semi-annular zone being transparent, said bulb having its front end provided with a translucent zone of relatively small area.

6. In a headlight, a converging reflector, in combination with an incandescent electric lamp having a bulb and translucent means for intercepting the direct rays from the source of light to the reflector at one side of the axis thereof from a point at the rear of the source of light to an arc throu h which the direct rays across the edge 0 the re flector pass.

7. In a headlight, in combination with a converging reflector, an incandescent electric lamp having means for projecting direct rays from the source to the field entirely around the axis of the reflector and also for projecting direct rays from said source to all points of the reflector, and means for subduing a portion of the direct rays in transit to the reflector at one side of the axis only.

8. In a headlight, in combination Witha converging reflector, an incandescent electric lamp having means for projecting direct rays from the source in diverging paths entirely around the produced axis of the reflector and also to all portions of said reflector around said axis, a translucent light intercepter at one side of the axis of the reflector, and at the rear of lines drawn from the source of light through the edge of the reflector, and an additional translucent light intercepter in said axis at the front of the source of light.

In Witness whereof I have hereunto set my hand this 24th day of December, 1914.

FREDRICK F. MACLEAN.

Witnesses:

H. E. CHASE, ALICE M. CANNON.

Copies of this patent may be obtained for five cents each, by addressing the Commissioner of Patents,

Washington, D. 0. 

